Fuel injection pump



June 1, 1965 H. HOGEMAN FUEL INJECTION PUMP Filed NOV. 15, 1963 FIGL' INVENTORZ HANS HOGEMAN W ATTYS.

United States Patent 3,186,344 FUEL INJECTION PUMP Hans Hogeman, Lcngmeadow, Mass, assignor to American Bosch Anna Corporation, Springfield, Mass, a corporation of New York Filed Nov. 13, 1963, Ser. No. 323,305 3 Claims. (Cl. 103-54) This application is a continuation-in-part application of my parent application entitled Fuel Injection Pump, filed June 14, 1961, and bearing Serial No. 125,326, now abandoned.

The present invention relates to improvements in fuel injection pumps for internal combustion engines or the like.

Fuel injection pumps for feeding fuel to cylinders of an internal combustion engine conventionally comprise a housing, fuel inlet and outlet means and a pumping and distributing member such as a plunger mounted for recipnocatin-g and rotational movement in the housing to deliver predetermined measured quantities of fuel to the cylinders of the engine. Usually the pump plunger is actuated by its own cam shaft which in turn is coupled to the main engine cam shaft.

An object of the present invention is to provide a novel fuel injection pump adapted to be mounted directly in an engine block whereby the fuel pumping and distributing plunger is actuated directly by cam and gear elements on the main engine cam shaft to provide a relatively compact and economical installation which obviates the need for the separate pump cam shaft and coupling connecting the pump cam shaft to the main engine cam shaft characteristic of prior pump installations.

A further object of the present invention is to provide a fuel injection pump for submerged mounting in an engine block including a novel lubricating system for lubricating internal moving parts or elements of the pump, the submerged mounting also facilitating splash lubrication of external parts of the pump from oil in the engine block during operation of the engine.

A still further object of the present invention is to provide a novel pump adapted for submerged mounting in an engine block whereby leakage from the pump to the exterior of the engine block is minimized.

A further object of the present invention is to provide a novel fuel injection pump of comparatively simplified construction which may be easily and economically manufactured and readily installed in an engine block conveniently and quickly.

These and other objects of the present invention and the various features and details of the construction and arangement of the pump and its mounting in an engine block are hereinafter more fully set forth with reference to the accompanying drawings, wherein:

FIG. 1 is a plan view showing a fuel injection pump in accordance with the present invention assembled in an engine block; and

FIG. 2 is an enlarged fragmentary sectional view taken on lines 22 of FIG. 1.

Referring now to the drawings and particularly to FIG. 2 thereof, there is shown a fuel injection pump P mounted on the hollow block 11 of an engine in which is mounted the main cam shaft 13 of the engine.

The pump comprises a generally cylindrical hollow housing 10, a head assembly 12 mounted in the housing and having a central bore 14 therethrough for a pumping and distributing member or plunger 16. The pump further includes a face gear 30 mounted in the lower portion of the housing 10 which is connected to the lower end of the plunger 16 by means of a key 32 and which is adapted to be rotated to rotate the plunger 16. A hollow tappet assembly 34 is mounted centrally of the face gear 30 as illustrated for axial movement upward against the bias of a spring 36 during the pump stroke of the plunger 16, the return stroke of the plunger being effected by the spring 36. As illustrated, the tappet 34 is of cup shaped configuration to define a spring chamber 39. By this arrangement as the plunger 16 is rotated and moved up and down by the face gear 30 and tappet assembly 34 respectively, fuel supplied through fuel inlet ports 19 and 20 is pumped in metered quantities through a delivery valve 25 to various fuel outlets H which communicate with the cylinders of the engine. It is noted that conventionally the number of outlets H is dependent on the number of cylinders of the engine, a single outlet H being provided for each engine cylinder.

In accordance with the present invention, the pump is adapted to be mounted in the engine block whereby actuation of the pumping and distributing plunger is effected directly through the main engine cam shaft. To this end, a generally circular opening 40 is provided in the engine block to receive the lower portion of the pump housing 10. To facilitate mounting of the pump in the engine block, the housing 10 is of stepped configuration defining an upper portion 10a and a lower portion 1% which, in the present instance, is of reduced cross section as illustrated to define a shoulder 42 engaging the block around the periphery of the opening 40. A peripheral flange 46 is provided at the juncture of the upper and lower portions of the pump housing 10 which has bolt holes 49 therein to receive bolts 51 for securing the pump to the engine block. The pump, as illustrated, depends into the housing to a depth so that the face gear meshes with a gear 50 on the engine cam shaft and the tappet assembly engages a cam 52 on the engine cam shaft. The cam 52 is provided with a number of lobes L according to the number of cylinders to be supplied by the pump, which lobes L upon rotation of the main engine cam shaft, drive the plunger 16 upwardly to pump fuel to the various engine cylinders supplied by the pump, the spring 36 returning the plunger and maintaining the tappet in engagement with the cam 52.

By submerging the pump P directly in the engine block 11, a simple, more compact overall installation is provided and the auxiliary cam shaft and the connection to the main engine cam shaft of prior installations is obviated. Another important advantage of this mounting arrangement is the fact that elements of the pump, such as the tappet and face gear, are lubricated during operation of the engine. In the present instance this is accomplished by providing an oil reservoir R defined by a shelf 53 in the engine block within which the gear 50 and cam 52 are partially immersed as illustrated in the drawing whereby upon rotation of the cam shaft 13, oil in the reservoir R is carried to the points of engagement of the cam 52 and gear 50 with the tappet 34 and face gear 30 respectively thereby producing splash lubrication of these engaging parts. If desired, these parts may be lubricated from the pressurized lubricating system of the engine by means of a fitting 63 in the engine block connected through a line 65 to the lube supply 61 of the system as indicated and located to direct lubricant in the area of engagement of the pump face gear 30 and tappet 34 with the cam shaft cam and gear.

Another feature of the present invention is the provision of means for lubricating some of the internal elements of the pump. To this end a circumferential cutout is formed in the Wall of the opening 40 in the engine block to define a continuous annular chamber 60 and a passageway 62 is provided in the engine block which is connected, for example, to the pressurized lubricating system 61 through line 67 to supply lubricant under pressure to the chamber 6t). A circular port 64 is provided in the lower portion 16 of the housing which is aligned with the chamber 64) and the face gear 30 includes a radial passageway 66 which communicates at its inner end with the spring chamber 39 and at its opposite outer end communicates with the port 64 in the housing once during every complete revolution of the face gear 30. By this arrangement, a charge of lubricant under pressure from the chamber 60 is admitted into the spring chamber 39 upon rotation of the face gear. An axial passage '70 in the face gear communicates with the radial passageway 66 to facilitate overflow when the spring chamber 39 is filled with excess lubricant. It is noted that the specific arrangement of the annular chamber 60 eliminates the need for precise positioning of the pump housing 16 in the engine block upon assembly.

While a particular embodiment of thepresent invention has been illustrated and described herein, it is not intended to limit the invention and changes and modifications will be made herein within the scope of the following claims.

I claim:

1. In combination, an engine including a hollow block having at least one opening therein and a main cam shaft mounted in said block, a fuel injection pump mounted in the opening in said block, said pump including a housing, a head assembly mounted in said housing and having a bore therethrough, fuel inlet and outlet means communicating with said bore, a fuel pumping and distributing member mounted in said bore, a face gear rotatably mounted in the lower portion of said housing connected to said pumping and distributing member to effect rotation thereof in said bore, a hollow tappet assembly mounted interiorly of said face gear adapted for axial movement therein to effect reciprocating axial movement of said pumping and distributing member in said bore, said bore pumping and distributing member upon reciprocating and rotating movement in said bore operable to deliver predetermined quantities of fuel from said fuel inlet to said fuel outlet means, means directly and operatively connecting said fuel pumping and distributing member to said cam shaft whereby actuation of said cam shaft effects reciprocating and rotating movement of said fuel pumping and distributing member through said face gear and said tappet assembly, means defining an annular chamber in the wall of said opening in said engine block, means for delivering a lubricant to said annular chamber, means defining a port in said pump housing communicating with said annular chamber, means defining a radial passageway in said face gear communicating at one end with the interior of said tappet assembly and at its opposite end communicating with said port in the pump housing once during every complete revolution of said face gear whereby lubricant from said annular chamber is fed to the interior of said tappet to lubricate internal parts of the pump.

2. The combination as claimed in claim 1, wherein the means directly connecting said pumping and distributing member to said cam shaft includes a cam on said shaft engaging said tappet assembly and a gear on said shaft meshing with said face gear and including a lubricant reservoir for lubricant in said engine block whereby upon rotation of said cam shaft, lubricant is splashed from said reservoir to external parts of the pump whereby external and internal elements of the pump are lubricated during operation of the engine.

3. In combination, an engine including a hollow block having at least one opening therein and a main cam shaft mounted in said block, a fuel injection pump mounted in the opening in said block, said pump including a housing, said pump housing being generally cylindrical having a lower portion of reduced cross section to define an annular shoulder at the juncture of the upper and lower portions of the housing adapted to seat on the engine block about the periphery of said opening therein and including a radial flange projecting from said shoulder having means for securing the pump to the engine block, a head assembly mounted in said housing and having a bore therethrough, fuel inlet and outlet means communicating with said bore, a fuel pumping and distributing member mounted in said bore, a face gear rotatably mounted in the lower portion of said housing connected to said pumping and distributing member to effect rotation thereof in said bore, a hollow tappet assembly mounted interiorly of said face gear adapted for axial movement therein to effect reciprocating axial movement of said pumping and distributing member in said bore, said pumping and distributing member upon reciprocating and rotating movement in said bore operable to deliver predetermined quantities of fuel from said fuel inlet to said fuel outlet means, means directly and operatively connecting said fuel pumping and distributing member to said cam shaft whereby actuation of said cam shaft effects reciprocating and rotating movement of said fuel pumping and distributing member through said face gear and said tappet assembly, means defining an annular chamber in the wall of said opening in said engine block, means for delivering a lubricant to said annular chamber, means defining a port in said pump housing communicating with said annular chamber, means defining a radial passageway in said face gear communicating at one end with the interior of said tappet assembly and at its opposite end communicating with said port in the pump housing once during every complete revolution of said face gear whereby lubricant from said annular chamber is fed to the interior of said tappet assembly to lubricate internal parts of the pump.

References Cited by the Examiner UNITED STATES PATENTS 2,383,749 8/45 Showers 12332 X 2,746,443 5/56 Meyer 103-2J1 X 2,980,092 4/61 Dreisin et a1 1032.1 X

FOREIGN PATENTS 966,708 9/57 Germany. 791,482 3/58 Great Britain.

LAURENCE V. FENER, Primary Examiner.

ROBERT M. WALKER, Examiner. 

1. IN COMBINATION, AN ENGINE INCLUDING A HOLLOW BLOCK HAVING AT LEAST ONE OPENING THEREIN AND A MAIN CAM SHAFT MOUNTED IN SAID BLOCK, A FUEL INJECTION PUMP MOUNTED IN THE OPENING IN SAID BLOCK, SAID PUMP INCLUDING A HOUSING, A HEAD ASSEMBLY MOUNTED IN SAID HOUSING AND HAVING A BORE THERETHROUGH, FUEL INLET AND OUTLET MEANS COMMUNICATING WITH SAID BORE, A FUEL PUMPING AND DISTRIBUTING MEMBER MOUNTED IN SAID BORE, A FACE GEAR ROTATABLY MOUNTED IN THE LOWER PORTION OF SAID HOUSING CONNECTED TO SAID PUMPING AND DISTRIBUTING MEMBER TO EFFECT ROTATION THEREOF IN SAID BORE, A HOLLOW TAPPET ASSEMBLY MOUNTED INTERIORLY OF SAID FACE GEAR ADAPTED FOR AXIAL MOVEMENT THEREIN TO EFFECT RECIPROCATING AXIAL MOVEMENT OF SAID PUMPING AND DISTRIBUTING MEMBER IN SAID BORE, SAID BORE PUMPING AND DISTRIBUTING MEMBER UPON RECIPROCATING AND ROTATING MOVEMENT IN SAID BORE OPERABLE TO DELIVER PREDETERMINED QUANTITIES OF FUEL FROM SAID FUEL INLET TO SAID FUEL OUTLET MEANS, MEANS DIRECTLY AND OPERATIVELY CONNECTING SAID FUEL PUMPING AND DISTRIBUTING MEMBER TO SAID CAM SHAFT WHEREBY ACTUATION OF SAID CAM SHAFT EFFECTS RECIPROCATING AND ROTATING MOVEMENT OF SAID FUEL PUMPING AND DISTRIBUTING MEMBER THROUGH SAID FACE GEAR AND SAID TAPPET ASSEMBLY, MEANS DEFINING AN ANNULAR CHAMBER IN THE WALL OF SAID OPENING IN SAID ENGINE BLOCK, MEANS FOR DELIVERING A LUBRICANT TO SAID ANNULAR CHAMBER, MEANS DEFINING A PORT IN SAID PUMP HOUSING COMMUNICATING WITH SAID ANNULAR CHAMBER, MEANS DEFINING A RADIAL PASSAGEWAY IN SAID FACE GEAR COMMUNICATING AT ONE END WITH THE INTERIOR OF SAID TAPPED ASSEMBLY AND AT ITS OPPOSITE END COMMUNICATING WITH SAID PORT IN THE PUMP HOUSING ONCE DURING EVERY COMPLETE REVOLUTION OF SAID FACE GEAR WHEREBY LUBRICANT FROM SAID ANNULAR CHAMBER IS FED IN THE INTERIOR OF SAID TAPPET TO LUBRICATE INTERNAL PARTS OF THE PUMP. 